Control device in particular for a carburetter throttle

ABSTRACT

For moving a throttle of a carburetter away from and elastically toward a given position. Device comprises a control means, a lever mounted relative to the support to pivot about an axis, an abutment fixed relative to the support, a first elastically yieldable return means connected to the lever to bias the lever in a direction to apply the lever against the abutment. Second elastically yieldable means are also employed and acts on a line which normally passes near said pivot axis. Lost-motion connecting means in parallel with the first return means is connected to the control means and to the lever.

United States Patent Beaumont et al. 1 1 Sept. 9, 1975 [541 CONTROL DEVICE IN PARTICULAR FOR A 3,699,943 10/1972 Eshelman 123/198 D 3,704,635 12/1972 Eshelman 1 123/198 D 3,731,667 5/1973 MacM1l1ar1.. 123/198 DB [75] Inventors: Robert Beaumont, Acheres; Bernard 3,791,366 2 1974 MacMilla1-| 123 198 DB Bertrand, Aubergenville, both of 3,830,213 8/1974 Herman 123/198 DB France 3,838,674 10/1974 Remaud 123/198 DB [731 Assignees: :33:12:: z ggfifs iigr Primary Examiner-Charles J. Myhre Boulo n Billancoun both Assistant Examiner-R. H. Lazarus g Attorney, Agent, or Firm--Burns, Doane, Swecker & France Mathis [22] Filed: May 21, 1973 21 Appl No.: 362,289 1 1 ABSTRACT For moving a throttle of a carburetter away from and [30] Foreign Application Priority Data elastically toward a given positlon. Device comprises a control means, a lever mounted relative to the support May 1972 Fran 7219463 to pivot about an axis, an abutment fixed relative to [972 France 724636 the support, a first elastically yieldable return means connected to the lever to bias the lever in a direction [52] 123/198 DB; 23 3 to apply the lever against the abutment Second elasti- [5 I] 3" g R Cally yieldable means are also employed and acts on a [58) F'eld Search 123/198 198 line which normally passes near said pivot axis. Lostmotion connecting means in parallel with the first re- [56] References C'ted turn means is connected to the control means and to UNITED STATES PATENTS the haven 3,626,919 12/1971 MacMillan 1. 123/198 DB 3,698,372 10/1972 Eshelman 123/198 D 10 Clams 4 D'awmg Fgures PATENTEU 95975 3,903,864

sum 2 0f 2 FIG.4

CONTROL DEVICE IN PARTICULAR FOR A CARBURETTER THROTTLE The present invention relates to a device for moving an element such as the throttle of a carburetter away from a given position and elastically returning it to said position.

When any mechanical element, which is made to move alternately in one direction and then in the other, is moved in one of the two directions by the action of an elastically yieldable return means, it is necessary to duplicate the return means as a precaution against breakage of the return means. In the event of breakage of one of the two return means, the other continues to perform the element-returning function. The main drawback of this arrangement is that, in normal operation, the positive actuating means by which the movable element can be shifted in opposition to the return means must overcome a force which is equal to at least twice that which would normally be necessary with a single return means.

An object of the present invention is to provide a device which ensures a correct return action in the event of breakage of the elastically yieldable return means which normally performs this function without substantially modifying the magnitude of the return force and consequently the magnitude of the force required to shift the movable element in the other direction.

This is obtained by means of a device in which the elastically yieldable return means is hooked to a lever mounted to pivot about an axis and biases the lever against an abutment, said lever being biased by a second elastically yieldable return means acting in a line which normally passes near to said pivot axis of the lever, a lost-motion connecting means being disposed in parallel with the first return means and connected to the movable element and to the lever.

In normal operation the return means applies the lever against a first abutment and tends to return the movable element to a given position against a second abutment.

Two embodiments of such a device and the operation and advantages thereof will be described in the ensuing description with reference to the accompanying drawings, given merely by way of example and in which:

FIG. I is a side elevational view ofa device according to the invention incorporated in a carburetter control;

FIG. 2 is a view similar to FIG. 1 of the device in two other operational positions;

FIG. 3 is an elevational view of a modification of the device according to the invention, and

FIG. 4 is a plan view of the device shown in FIG. 3.

FIGS. 1 and 2 show a carburetter body I in which is mounted to pivot about a spindle 2 a throttle 3 integral with a lever 4 which is shifted by a pedal or rod 5 controlled by a user. This lever 4, rotated in the direction of arrow F, by the cable 5, is returned in the opposite direction against an abutment 6 under the action of an elastically yieldable return means constituted by a spring 7.

At its other end, the spring 7 is hooked to a lever 8 mounted to pivot about a pivot pin 9 on a suitable fixed part, for example the engine with which the carburetter is associated. The lever 8 comprises a cranked end portion 10 to which is hooked a second elastically yieldable return means constituted by a spring I].

The lever 8 is normally applied against an abutment 12 and in this position of normal operation this lever is substantially perpendicular to the spring 7 whereas the second spring 11 is roughly parallel to the main branch of the lever 8 so that its line of action passes very near to the pivot pin 9. Moreover, the two levers 4 and 8 are interconnected by a lost-motion or limited-motion mechanism constituted in the presently-described embodiment by a cylinder 13 hooked to the lever 8 and a rod 14 hooked to the lever 4. The rod 14 extends through the end wall 15 of the cylinder and has inside the latter a shoulder 16 which abuts the end wall of the cylinder after a given travel. This mechanism, constituted by the cylinder and the rod, is disposed substantially parallel to the first return spring 7.

Such a device operates in the following manner:

In normal operation, the torques produced on the lever 8 by the springs 7 and 11 are in opposite directions but, bearing in mind that the line of action of the spring 11 passes relatively near to the pivot pin 9 of the lever 8, the torque produced by the spring 7 is distinctly predominant and maintains the lever 8 in abutment against the abutment 12. Under these conditions, only the spring 7 acts for returning the lever 4 to a position of abutment against the abutment 6 when the pull exerted on the cable 5 decreases or ceases completely. The dimensions of the cylinder 13 and rod 14 are such that this mechanism intervenes in no way in this stage of operation.

If, as shown in full line in FIG. 2, the spring 7 breaks or becomes unhooked when the lever 4 has been driven by the cable 5 in the direction of arrow F, to the vicin ity ofits extreme position corresponding to the opening of the throttle 3, the lever 8, which is only biased by the second spring 11, rotates about its pivot pin in moving away from its abutment 12 until the shoulder 16 of the rod 14 abuts the end wall 15 of the cylinder I3. This movement has for effect to increase the distance between the pivot pin 9 and the line of action of the second spring 11 and consequently to increase the torque exerted by the latter on the lever 8. Thus, when the tensile force exerted on the cable 5 is released, the lever 4 is returned against the abutment 6 by the action of the spring ll exerted through the lever 8, the cylinder 13 and the rod 14.

It can be seen, therefore, that the relatively simple means employed ensures operation notwithstanding breakage of the main return spring without correspondingly increasing the return force in normal operation since the force exerted by the second spring 11 on the lever 8 has practically no effect on the return force exerted by the main spring 7.

Moreover, it can be seen that when the assembly has been returned to the position of rest shown in dot-dash line in FIG. 2, the line of action of the spring II has been moved still further away from the pivot pin 9 and this increases the torque exerted on the lever 8. This torque may be chosen in such manner that the force exerted on the cable 5 for shifting once more the lever 4 exceeds the force normally required so as to warn the user of the breakage of the main spring 7.

This device has been described in its application to the control of a throttle of a carburetter, but it will be understood that the device can be employed whatever he the type of the movable element which must be returned to a given position of rest.

FIGS. 3 and 4 show a carburetter body 2I in which a throttle 22 is mounted on a shaft 23 integral with a reel 24. Secured to the latter is the end of a cable 25 which is wound partly in a groove 26 in the reel and leads to the accelerator pedal (not shown), it extending through a sheath 27 whose end bears against an abutment 28 of a member 29 secured to the carburetter body 21.

The reel 24 is driven in the direction of arrow F by the cable 25 and is returned in the opposite direction by a coil spring 30 which operates under torsion and has one end engaged in a groove 31 in the reel and its opposite end bears against a tab 32 of a lever 33. The latter is mounted to pivot about a pin 34 and is normally stopped by engagement of its tab 32 against an abutment 35 formed on the member 29. The lever 33 has in the presently-described embodiment the shape of a hook and thus extends partly around the shaft 23 of the carburetter throttle. This shape or a like shape enables the lever 33 to be placed between the body 21 and the reel 24 and thus affords minimum overall size.

A second spring 36, disposed between and connected to a tab 37 of the lever 33 and a tab 28 of the member 29, exerts on the lever 33 a torque which is opposite to but less than that exerted by the spring 30.

A finger member 39 secured to the reel 24 is engaged in an opening 40 formed in the lever 33 so as to constitute the lostmotion connecting mechanism. Thus, in this embodiment, the lever 33 has the shape of a hook one end of which is normally maintained against the abutment 35 by the spring 30 whereas its opposite end includes the opening 40 of the lost-motion mechanism, the pivot pin 34 being located between these two ends.

The device just described operates in a similar manner to that described hereinbefore.

In normal operation, the lever 33 occupies the posi tion shown in full line in FIG. 3, that is to say, it is maintained in abutment against' the tab 35 by the return spring 30. When the user exerts a pull on the cable 25, the reel 34 rotates in the direction of arrow F, (FIG. 3) and thus rotates the shaft 23 and the throttle of the carburetter. The throttle is returned to its idling speed position by the spring 30. In the course of these movements, the finger member 39 moves freely in the opening 40 and the action of the spring 36 is without effect on the lever 33 owing to the fact that the torque it exerts on this lever is less than the torque exerted in the opposite direction by this lever on the spring 30.

In the event of breakage or unhooking of the return spring 30, the latter no longer maintains the lever 33 applied against the abutment 35 so that the spring 36 acts to rotate the lever 33 and brings it to the illustrated position shown in dot-dash line in FIG. 3. As soon as this displacement has started, the line of action of the Spring 36 moves away from the pivot pin 34 of the lever 33 so that the effect of this spring becomes progressively greater. The rotation of the lever 33 has for effect to bring the lower end (as viewed in FIG. 3) of the opening 40 into abutment against the finger member 39 so that the latter is driven in the direction for returning the carburetter throttle to its normal idling speed position.

It can be seen that in such an embodiment, in addition to the advantages already mentioned, the fact of making the member 29 perform several functions and of incorporating in the lever 33 a part of the lostmotion mechanism, substantially reduces the number of parts, facilitates the assembly of the device on a carburetter of conventional type and renders the device more reliable.

Having now described our invention what We claim as new and desire to secure by Letters Patent is:

l. A control device for moving a throttle of a carburetter away from a given position and elastically returning the throttle to said given position, comprising a carburetter body, a control element movably mounted relative to said body and connected to move the throttle, shifting means for shifting the control element, a lever mounted to pivot relative to said body about a pivot axis, a fixed element integral with said body and defining an abutment, a first elastically yieldable return means connected to the lever and to bias the lever in a direction to apply the lever against the abutment, the lever having a first portion which is normally disposed between the first return means and the fixed element and a second portion, a second elastically yieldable return means connected to the lever and disposed relative to the lever to act in a line which normally passes near said pivot axis, and lost-motion connecting means operatively connected, to act in parallel with the first return means, to the control element and to the lever, the second portion of the lever being part of the lostmotion connecting means, said lost motion connecting means for operatively connecting the second return means to the throttle when the first return means fails.

2. A device as claimed in claim 1, wherein when the lever is applied against its abutment, the lever and the second yieldable means are substantially parallel to each other and perpendicular to the first yieldable means.

3. A device as claimed in claim I, wherein the connecting means comprises a hollow member connected to one of two members consisting of said control element and said lever, a rod connected to the other of said two members and slidably mounted in the hollow member and having on an end of the rod received in the hollow member stop means, and complementary stop means on the hollow member for abutment against the rod stop means after a given travel of the rod relative to the hollow member.

4. A device as claimed in claim 1, wherein the fixed member also includes hooking means for the second elastically yieldable return means.

5. A device as claimed in claim 4, wherein the second elastically yieldable return means is hooked to the member integral with the body and exerts on the lever a torque which is opposite to and less in absolute value than that exerted by the first yieldable return means on the lever.

6. A control device for moving a throttle of a carburetter away from a given position and elastically returning the throttle to said given position, comprising a carburetter'body, a control element movably mounted relative to said body and connected to move the throttle, shifting means for shifting the control element, a lever mounted to pivot relative to said body about a pivot axis, a fixed element integral with said body and defining an abutment, a first elastically yieldable return means connected to the lever and to bias the lever in a direction to apply the lever against the abutment, the lever having a first portion which is normally disposed between the first return means and the fixed element and a second portion, a second elastically yieldable return means connected to the lever and disposed relative to the lever to act in a line which normally passes near said pivot axis. and lost-motion connecting means operatively connected, to act in parallel with the first return means, to the control element and to the lever. the second portion of the lever being part of the lostmotion connecting means, the control element being a reel and the shitting means comprising a cable which is attached to the reel and the first return means being attached to the reel. the lost-motion connecting means comprising means defining an opening and a lug. one of two elements consisting of the means defining the opening and the lug being carried by the second portion of the lever and the other of said two elements being carried by the reel.

7. A device as claimed in claim 6, wherein the second portion of the lever defines said opening and the lug is carried by the reel.

8. A device as claimed in claim 1, wherein the throttle is carried by a shaft and the lever extends at least partially around the shaft.

9. A device as claimed in claim 8, wherein the lever has substantially the shape of a hook one end portion of which hook constitutes said first portion and an opposite end portion of which hook constitutes said second portion.

10. A device as claimed in claim 1, wherein the shifting means comprise a cable in a sheath and the fixed element is combined with the sheath to support the sheath.

I l l i I 

1. A control device for moving a throttLe of a carburetter away from a given position and elastically returning the throttle to said given position, comprising a carburetter body, a control element movably mounted relative to said body and connected to move the throttle, shifting means for shifting the control element, a lever mounted to pivot relative to said body about a pivot axis, a fixed element integral with said body and defining an abutment, a first elastically yieldable return means connected to the lever and to bias the lever in a direction to apply the lever against the abutment, the lever having a first portion which is normally disposed between the first return means and the fixed element and a second portion, a second elastically yieldable return means connected to the lever and disposed relative to the lever to act in a line which normally passes near said pivot axis, and lost-motion connecting means operatively connected, to act in parallel with the first return means, to the control element and to the lever, the second portion of the lever being part of the lost-motion connecting means, said lost motion connecting means for operatively connecting the second return means to the throttle when the first return means fails.
 2. A device as claimed in claim 1, wherein when the lever is applied against its abutment, the lever and the second yieldable means are substantially parallel to each other and perpendicular to the first yieldable means.
 3. A device as claimed in claim 1, wherein the connecting means comprises a hollow member connected to one of two members consisting of said control element and said lever, a rod connected to the other of said two members and slidably mounted in the hollow member and having on an end of the rod received in the hollow member stop means, and complementary stop means on the hollow member for abutment against the rod stop means after a given travel of the rod relative to the hollow member.
 4. A device as claimed in claim 1, wherein the fixed member also includes hooking means for the second elastically yieldable return means.
 5. A device as claimed in claim 4, wherein the second elastically yieldable return means is hooked to the member integral with the body and exerts on the lever a torque which is opposite to and less in absolute value than that exerted by the first yieldable return means on the lever.
 6. A control device for moving a throttle of a carburetter away from a given position and elastically returning the throttle to said given position, comprising a carburetter body, a control element movably mounted relative to said body and connected to move the throttle, shifting means for shifting the control element, a lever mounted to pivot relative to said body about a pivot axis, a fixed element integral with said body and defining an abutment, a first elastically yieldable return means connected to the lever and to bias the lever in a direction to apply the lever against the abutment, the lever having a first portion which is normally disposed between the first return means and the fixed element and a second portion, a second elastically yieldable return means connected to the lever and disposed relative to the lever to act in a line which normally passes near said pivot axis, and lost-motion connecting means operatively connected, to act in parallel with the first return means, to the control element and to the lever, the second portion of the lever being part of the lost-motion connecting means, the control element being a reel and the shifting means comprising a cable which is attached to the reel and the first return means being attached to the reel, the lost-motion connecting means comprising means defining an opening and a lug, one of two elements consisting of the means defining the opening and the lug being carried by the second portion of the lever and the other of said two elements being carried by the reel.
 7. A device as claimed in claim 6, wherein the second portion of the lever defines said opening and the lug is carried by the reel.
 8. A device as claimed in claim 1, wherein the throttle is carried by a shaft and the lever extends at least partially around the shaft.
 9. A device as claimed in claim 8, wherein the lever has substantially the shape of a hook one end portion of which hook constitutes said first portion and an opposite end portion of which hook constitutes said second portion.
 10. A device as claimed in claim 1, wherein the shifting means comprise a cable in a sheath and the fixed element is combined with the sheath to support the sheath. 